Originally Posted By: JHZR2
Originally Posted By: slacktide_bitog
Aftermarket cats are not a problem as long as you're not burning oil
Yes they are. The washcoat when new is barely good enough to squeak by and pass emissions.
I had a bad NOx catalyst in my older BMW (no EGR), and so I swapped the cat, the results were literally a few PPM lower, just enough to squeak by.
OE cat had me from around 1100ppm with old and replacement aftermarket, to 11ppm!
Exactly, its the wash coat that does the work. CA certified cats have more of it, not OE level but enough to at least function for about 50-75K. The flanges usually rot off before that anyway in the salt belt.
Originally Posted By: slacktide_bitog
Aftermarket cats are not a problem as long as you're not burning oil
Yes they are. The washcoat when new is barely good enough to squeak by and pass emissions.
I had a bad NOx catalyst in my older BMW (no EGR), and so I swapped the cat, the results were literally a few PPM lower, just enough to squeak by.
OE cat had me from around 1100ppm with old and replacement aftermarket, to 11ppm!
Exactly, its the wash coat that does the work. CA certified cats have more of it, not OE level but enough to at least function for about 50-75K. The flanges usually rot off before that anyway in the salt belt.